Since we’ve launched a “mixed model” feature I get at least one email about it every day. Sometimes it’s because the mechanics of it are relatively complicated. This is something that can be and will be addressed over time.
Most of the times, however, the questions in the emails are based on the assumption that AdDuplex is a monetization platform for apps. I’m sorry to disappoint a number of users, but it’s not. AdDuplex is a self/cross promotion platform first and foremost. The mixed model (aka monetization) feature is only a bonus add-on for the main purpose of the system.
The point is: if you don’t value the promotion of your app at least as much as money you can get from the ads, then AdDuplex is most likely not the right choice for you. There’s no option to participate in the monetization part of the system without participating in the exchange part. And there are no plans to change that concept in the nearest future.
I understand that this explanation may turn some developers away from AdDuplex, but I’d rather see them happy elsewhere, than unhappy over here. Everything has it’s purpose and everything has to solve some problem for someone. AdDuplex aims to solve the free app promotion and exposure problem. If this is something that you need you are very welcome. You may even make some money in the process!